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Exact Solution for a Class of Stiff Systems by Differential Transform Method

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Applied Mathematics 2013年第3期4卷 440-444页

作者： Muhammad idrees Fazle Mabood Asar Ali Gul zaman City University of Science and Information Technology Peshawar Pakistan Edwardes College Peshawar Pakistan University of Malakand Chakdara Dir (Lower) Pakistan

In this paper, Differential Transform Method (DTM) is proposed for the closed form solution of linear and non-linear stiff systems. First, we apply DTM to find the series solution which can be easily converted into exact solution. The method is described and illustrated with different examples and figures are plotted accordingly. The obtained result confirm that DTM is very easy, effective and convenient.

关键词： Differential Transform Method Stiff System Inverse Differential Transform

Growth and Physiological Performance of Aerobic and Lowland Rice as Affected by Water Stress at Selected Growth Stages

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Rice science 2018年第2期25卷 82-93页

作者： Nadzariah Kamarul zaman Mohd Yusoff ABDULLAH Sariam OTHMAN Nadzirah Kamarul zaman Ecophysiology Research Group Faculty of Plantation and Agrotechnology Universiti Teknologi MARA Shah Alam Selangor 40450 Malaysia Malaysian Agriculture and Research Development Institute Serdang Selangor 43400 Malaysia

Aerobic rice technology is still new in Malaysia, and information regarding MARDI Aerob 1(MA1), the first local aerobic rice variety, is still lacking. Therefore, comparative studies were carried out to determine the physiological performance of aerobic rice variety MA1 and lowland rice variety MR253 under water stress given at the panicle initiation, flowering and ripening stages. This experiment was arranged in a randomized complete block design. Stomatal conductance(g_s), chlorophyll a fluorescence(F_v/F_m), leaf relative water content(leaf RWC), and soil moisture content(SMC) as well as yield component parameters such as panicle number, grain yield and 100-grain weight were measured. Results revealed that gs and leaf RWC for both varieties decreased with depletion of SMC. The correlation study between the physiological parameters and SMC indicated that F_v/F_m was not affected by water stress, regardless of varieties. The yield components(panicle number, grain yield and 100-grain weight) for both varieties greatly decreased when water stress was imposed at the panicle initiation stage. This study showed that the panicle initiation period was the most sensitive stage to water stress that contributed to a substantial reduction in yield for both varieties. Under the aerobic condition(control), MR253 produced higher panicle number, 100-grain weight and yield than MA1. Although MR253 is bred for lowland, it is well adapted to aerobic condition.

关键词： water stress stomatal conductance chlorophyll a fluorescence leaf relative water content yield component aerobic rice

Prediction of corrosion rate for friction stir processed WE43 alloy by combining PSO-based virtual sample generation and machine learning

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Journal of Magnesium and Alloys 2024年第4期12卷 1518-1528页

作者： Annayath Maqbool Abdul Khalad Noor zaman Khan Department of Mechanical Engineering National Institute of Technology SrinagarJ&K 190006India Department of Mechanical Engineering Indian Institute of TechnologyHyderabadSangareddyTelangana 502284India School of Engineering Deakin UniversityVictoria 3216Australia

The corrosion rate is a crucial factor that impacts the longevity of materials in different *** undergoing friction stir processing(FSP),the refined grain structure leads to a notable decrease in corrosion ***,a better understanding of the correlation between the FSP process parameters and the corrosion rate is still *** current study used machine learning to establish the relationship between the corrosion rate and FSP process parameters(rotational speed,traverse speed,and shoulder diameter)for WE43 *** Taguchi L27 design of experiments was used for the experimental *** addition,synthetic data was generated using particle swarm optimization for virtual sample generation(VSG).The application of VSG has led to an increase in the prediction accuracy of machine learning models.A sensitivity analysis was performed using Shapley Additive Explanations to determine the key factors affecting the corrosion *** shoulder diameter had a significant impact in comparison to the traverse speed.A graphical user interface(GUI)has been created to predict the corrosion rate using the identified *** study focuses on the WE43 alloy,but its findings can also be used to predict the corrosion rate of other magnesium alloys.

关键词： Corrosion rate Friction stir processing Virtual sample generation Particle swarm optimization Machine learning Graphical user interface

Analyzing uncertainties involved in estimating collapse risk with and without considering uncertainty probability distribution parameters

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Earthquake Engineering and Engineering Vibration 2022年第1期21卷 101-116页

作者： Mohammad Amin Bayari Naser Shabakhty Esmaeel Izadi zaman Abadi Department of Civil Engineering Najafabad BranchIslamic Azad UniversityNajafabad ***Iran School of Civil Engineering Iran University of Science and TechnologyTehran 16844Iran

In the present study,modified Ibarra,Medina and Krawinkler moment-rotation parameters are used for modeling the uncertainties in concrete moment frame *** of model parameters in a component and between two structural components were considered to analyze these *** the first step,the structural collapse responses were obtained by producing 281 samples for the uncertainties using the Latin hypercube sampling(LHS)method,considering the probability distribution of the uncertainties and performing incremental dynamic *** the second step,281 new samples were produced for the uncertainties by the central composite design(CCD)method without considering the probability distribution of the uncertainties and calculating the structural collapse ***,using the response surface method(RSM)and artificial neural network(ANN)for the two simulation modes,structural collapse responses were *** results indicated that the collapse responses at levels of 0 to 100%obtained from the two simulations have a high correlation coefficient of 98%.This suggests that random variables can be simulated without considering the probability distribution of uncertainties,by performing uncertainty analysis to determine structural collapse responses.

关键词： uncertainty analysis collapse response artificial neural network response surface method

AN INVESTIGATION OF THE RELATION BETWEEN COTTON FIBRE PROPERTIES AND YARN QUALITY BY USING HIGH VOLUME INSTRUMENT(HVI)SYSTEM

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Journal of China Textile University(English Edition) 1993年第2期10卷 7-13页

作者： M.A.zaman 储才元严灏景 Dept.of Textile Engineering

The objective of this paper is to establish reliable prediction equations relating cotton fibreproperties measured by HVI system and yarn quality,A useful statistical method is adopted for de-veloping a multiple regression model interpreting the relation between the data of Spinlab HVIfibre properties and quality parameters of yarn STQ (Strength Tex Quotient).The percent relativecontribution of a fibre property with respect of STQ is also *** results show that the totalcontribution of the HVI measured fibre properties can account for 77.4% of known variation ofyarn *** main feature of the approach is its flexibility in accommodating all fibre *** examination of regression equation showed that it could be well applied to predict STQ ofyarns spun from the same spinning system,but,for different spinning systems and also for yarns ofdifferent linear density,modification of the equation would be needed.

关键词： regression analysis correlations cotton fibres fibre properties cotton yarn yarn properties ring spinning High Volume Instrument

Magnetic CuO nanoparticles supported on graphene oxide as an efficient catalyst for A^3-coupling synthesis of propargylamines

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Chinese Chemical Letters 2015年第9期26卷 1085-1090页

作者： Maryam Mirabedini Elaheh Motamedi Mohammad zaman Kassaee Department of Chemistry Tarbiat Modares University Department of Food Nanotechnology Research Institute of Food Science and Technology(RIFST)

Magnetically separable CuO nanoparticles supported on graphene oxide（Fe3O4 NPs/GO-CuO NPs） is synthesized and characterized for the preparation of propargylamines in EtOH,at 90 ***3O4 NPs/GOCuO NPs is found to be an efficient catalyst for the A^3-coupling of aldehydes,amines,and alkynes through C-H *** aromatic and aliphatic aldehydes and alkynes are combined with secondary amines to provide a wide range of propargylamines in moderate to excellent yields.

关键词： CuO Graphene oxide Fe3O4 A^3-coupling Nano-catalyst Magnetic nanoparticles

Thermally stratified flow of hybrid nanofluids with radiative heat transport and slip mechanism: multiple solutions

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Communications in Theoretical Physics 2022年第1期74卷 142-151页

作者： Rai Sajjad Saif Hashim Maria zaman Muhammad Ayaz Department of Humanities and Sciences School of Electrical Engineering and Computer Science(SEECS)National University of Sciences and Technology(NUST)IslamabadPakistan Department of Pure&Applied Mathematics University of Haripur22620HaripurPakistan Department of Mathematics&Statistics Riphah International University IslamabadPakistan Department of Mathematics Abdul Wali Khan UniversityMardan23200Pakistan

Research on flow and heat transfer of hybrid nanofluids has gained great significance due to their efficient heat transfer *** fact,hybrid nanofluids are a novel type of fluid designed to enhance heat transfer rate and have a wide range of engineering and industrial *** by this evolution,a theoretical analysis is performed to explore the flow and heat transport characteristics of Cu/Al_(2)O_(3) hybrid nanofluids driven by a stretching/shrinking ***,this work focuses on the physical impacts of thermal stratification as well as thermal radiation during hybrid nanofluid flow in the presence of a velocity slip *** mathematical modelling incorporates the basic conservation laws and Boussinesq *** formulation gives a system of governing partial differential equations which are later reduced into ordinary differential equations via dimensionless *** efficient numerical solver,known as bvp4c in MATLAB,is utilized to acquire multiple(upper and lower)numerical solutions in the case of shrinking *** computed results are presented in the form of flow and temperature *** most significant findings acquired from the current study suggest that multiple solutions exist only in the case of a shrinking surface until a critical/turning ***,solutions are unavailable beyond this turning point,indicating flow *** is found that the fluid temperature has been impressively enhanced by a higher nanoparticle volume fraction for both *** the other hand,the outcomes disclose that the wall shear stress is reduced with higher magnetic field in the case of the second *** simulation outcomes are in excellent agreement with earlier research,with a relative error of less than 1%.

关键词： multiple numerical solutions hybrid nanofluids thermal radiation thermal stratification slip conditions heat transfer

Role of Ca^(2+) on Growth of Brassica campestris *** ***(L.) Czern & Coss under Na^+ Stress

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Journal of Integrative Plant Biology 2010年第6期52卷 549-555页

作者： Badr-uz-zaman M.Salim Rehana Asghar Land Resources Research Programme Institute of Natural Resources and Environmental SciencesNational Agricultural Research Centre Department of Botany University of Arid Agriculture

Root and shoot growth of Brassica campestris L. and B. juncea increased significantly （P 〈 0.01） with enhanced Ca2＋ treatment along with 60 mM NaCl in the root medium. The maximum fresh mass of shoot and root in *** was recorded at 10 mM Ca2＋ concentration. The relative growth rate of shoot of both species reached its maximum at 8 mM of Ca2＋ concentration. Average rate of Ca2＋ intake （lCa） was higher in B. juncea than 6. campestris. In B. juncea, the average transport of Ca2＋ to shoot increased by 19%, 38%, 119%, 125% and 169% compared with the control. Furthermore specific utilization rate of Ca2＋ was higher in B. juncea than B. campestris. In B. campestris it increased by 9%, 32%, 41% and 59% at 4, 6, 8, and 10 mM of calcium in comparison to 2 mM Ca2＋ treatment. At 4, 6, 8 and 10 mM of Ca2＋ application, the increase in the leaf area ratio was 10,17, 23 and 30%, respectively. In the shoot and root portions of B. campestris and ***, Ca2＋ had a linear relationship with potassium and sulfur, whereas it was in antagonism with sodium ion.

关键词： Coss under Na Czern Stress

Four-dimensional parameter estimation of plane waves using swarming intelligence

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Chinese Physics B 2014年第7期23卷 754-761页

作者： Fawad zaman Ijaz Mansoor Qureshi Fahad Munir Zafar Ullah Khan Department of Electronic Engineering Faculty of Engineering and Technology International Islamic University Sector H-10 Department of Electrical Engineering Air University

This paper proposes an efficient approach for four-dimensional （4D） parameter estimation of plane waves impinging on a 2-L shape array. The 4D parameters include amplitude, frequency and the two-dimensional （2D） direction of arrival, namely, azimuth and elevation angles. The proposed approach is based on memetic computation, in which the global optimizer, particle swarm optimization is hybridized with a rapid local search technique, pattern search. For this purpose, a new multi-objective fitness function is used. This fitness function is the combination of mean square error and the correlation between the normalized desired and estimated vectors. The proposed hybrid scheme is not only compared with individual performances of particle swarm optimization and pattern search, but also with the performance of the hybrid genetic algorithm and that of the traditional approach. A large number of Monte-Carlo simulations are carried out to validate the performance of the proposed scheme. It gives promising results in terms of estimation accuracy, convergence rate, proximity effect and robustness against noise.

关键词： amplitude estimation direction of arrival estimation frequency estimation genetic algorithm